Chemistry of Small Metal Cluster Ions

Abstract

Abs. cross sections are reported for reactions of small Al cluster ions (Al1-5+) with Ar, O2 and D2O. Dependence of reactivity on cluster size and collision energy was measured in a tandem mass spectrometer equipped with radio frequency ion guides and a unique source of thermalized metal cluster ions. Reactions of even small Al cluster ions with simple reagent mols. under single collision conditions can be quite complex, resulting in several significant reaction channels. At low collision energies, exoergic prodn. of oxide, hydroxide, and hydrate products is important, esp. for small clusters. At high collision energies prodn. of bare Al fragment ions proceeds through a mechanism which appears similar to simple collision-induced dissocn. These results emphasize the importance of being able to measure accurate cross sections over a range of collision energies in studies of reaction mechanisms. [on SciFinder (R)]